Inhaled antibiotics: A promising drug delivery strategies for efficient treatment of lower respiratory tract infections (LRTIs) associated with antibiotic resistant biofilm-dwelling and intracellular bacterial pathogens

Antibiotic-resistant bacteria associated with LRTIs are frequently associated with inefficient treatment outcomes. Antibiotic-resistant Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, and Staphylococcus aureus, infections are strongly associated with pulmonary exacerbations and require frequent hospital admissions, usually following failed management in the community. These bacteria are difficult to treat as they demonstrate multiple adaptational mechanisms including biofilm formation to resist antibiotic threats. Currently, many patients with the genetic disease cystic fibrosis (CF), non-CF bronchiectasis (NCFB) and chronic obstructive pulmonary disease (COPD) experience exacerbations of their lung disease and require high doses of systemically administered antibiotics to achieve meaningful clinical effects, but even with high systemic doses penetration of antibiotic into the site of infection within the lung is suboptimal. Pulmonary drug delivery technology that reliably deliver antibacterials directly into the infected cells of the lungs and penetrate bacterial biofilms to provide therapeutic doses with a greatly reduced risk of systemic adverse effects. Inhaled liposomal-packaged antibiotic with biofilm-dissolving drugs offer the opportunity for targeted, and highly effective antibacterial therapeutics in the lungs. Although the challenges with development of some inhaled antibiotics and their clinicals trials have been studied; however, only few inhaled products are available on market. This review addresses the current treatment challenges of antibiotic-resistant bacteria in the lung with some clinical outcomes and provides future directions with innovative ideas on new inhaled formulations and delivery technology that promise enhanced killing of antibiotic-resistant biofilm-dwelling bacteria.

Deciphering the microbial landscape of lower respiratory tract infections: insights from metagenomics and machine learning

Background

Lower respiratory tract infections represent prevalent ailments. Nonetheless, current comprehension of the microbial ecosystems within the lower respiratory tract remains incomplete and necessitates further comprehensive assessment. Leveraging the advancements in metagenomic next-generation sequencing (mNGS) technology alongside the emergence of machine learning, it is now viable to compare the attributes of lower respiratory tract microbial communities among patients across diverse age groups, diseases, and infection types.

Method

We collected bronchoalveolar lavage fluid samples from 138 patients diagnosed with lower respiratory tract infections and conducted mNGS to characterize the lung microbiota. Employing various machine learning algorithms, we investigated the correlation of key bacteria in patients with concurrent bronchiectasis and developed a predictive model for hospitalization duration based on these identified key bacteria.

Result

We observed variations in microbial communities across different age groups, diseases, and infection types. In the elderly group, Pseudomonas aeruginosa exhibited the highest relative abundance, followed by Corynebacterium striatum and Acinetobacter baumannii. Methylobacterium and Prevotella emerged as the dominant genera at the genus level in the younger group, while Mycobacterium tuberculosis and Haemophilus influenzae were prevalent species. Within the bronchiectasis group, dominant bacteria included Pseudomonas aeruginosa, Haemophilus influenzae, and Klebsiella pneumoniae. Significant differences in the presence of Pseudomonas phage JBD93 were noted between the bronchiectasis group and the control group. In the group with concomitant fungal infections, the most abundant genera were Acinetobacter and Pseudomonas, with Acinetobacter baumannii and Pseudomonas aeruginosa as the predominant species. Notable differences were observed in the presence of Human gammaherpesvirus 4, Human betaherpesvirus 5, Candida albicans, Aspergillus oryzae, and Aspergillus fumigatus between the group with concomitant fungal infections and the bacterial group. Machine learning algorithms were utilized to select bacteria and clinical indicators associated with hospitalization duration, confirming the excellent performance of bacteria in predicting hospitalization time.

Conclusion

Our study provided a comprehensive description of the microbial characteristics among patients with lower respiratory tract infections, offering insights from various perspectives. Additionally, we investigated the advanced predictive capability of microbial community features in determining the hospitalization duration of these patients.

Comparative microbiome analysis in cystic fibrosis and non-cystic fibrosis bronchiectasis

BACKGROUND

Bronchiectasis is a condition characterized by abnormal and irreversible bronchial dilation resulting from lung tissue damage and can be categorized into two main groups: cystic fibrosis (CF) and non-CF bronchiectasis (NCFB). Both diseases are marked by recurrent infections, inflammatory exacerbations, and lung damage. Given that infections are the primary drivers of disease progression, characterization of the respiratory microbiome can shed light on compositional alterations and susceptibility to antimicrobial drugs in these cases compared to healthy individuals.

METHODS

To assess the microbiota in the two studied diseases, 35 subjects were recruited, comprising 10 NCFB and 13 CF patients and 12 healthy individuals. Nasopharyngeal swabs and induced sputum were collected, and total DNA was extracted. The DNA was then sequenced by the shotgun method and evaluated using the SqueezeMeta pipeline and R.

RESULTS

We observed reduced species diversity in both disease cohorts, along with distinct microbial compositions and profiles of antimicrobial resistance genes, compared to healthy individuals. The nasopharynx exhibited a consistent microbiota composition across all cohorts. Enrichment of members of the Burkholderiaceae family and an increased Firmicutes/Bacteroidetes ratio in the CF cohort emerged as key distinguishing factors compared to NCFB group. Staphylococcus aureus and Prevotella shahii also presented differential abundance in the CF and NCFB cohorts, respectively, in the lower respiratory tract. Considering antimicrobial resistance, a high number of genes related to antibiotic efflux were detected in both disease groups, which correlated with the patient's clinical data.

CONCLUSIONS

Bronchiectasis is associated with reduced microbial diversity and a shift in microbial and resistome composition compared to healthy subjects. Despite some similarities, CF and NCFB present significant differences in microbiome composition and antimicrobial resistance profiles, suggesting the need for customized management strategies for each disease.

Bronchiectasis with Chronic Rhinosinusitis Is Associated with Eosinophilic Airway Inflammation and Is Distinct from Asthma

Rationale: Bronchiectasis is an airway inflammatory disease that is frequently associated with chronic rhinosinusitis (CRS). An eosinophilic endotype of bronchiectasis has recently been described, but detailed testing to differentiate eosinophilic bronchiectasis from asthma has not been performed. Objectives: This prospective observational study aimed to test the hypotheses that bronchiectasis with CRS is enriched for the eosinophilic phenotype in comparison with bronchiectasis alone and that the eosinophilic bronchiectasis phenotype exists as a separate entity from bronchiectasis associated with asthma. Methods: People with idiopathic or postinfectious bronchiectasis were assessed for concomitant CRS. We excluded people with asthma or primary ciliary dyskinesia and smokers. We assessed sputum and blood cell counts, nasal NO and fractional excreted NO, methacholine reactivity, skin allergy testing and total and specific immunoglobulin (Ig) E, cytokines in the sputum and serum, and the microbiome in the sputum and nasopharynx. Results: A total of 22 people with CRS (BE + CRS) and 17 without CRS (BE - CRS) were included. Sex, age, Reiff score, and bronchiectasis severity were similar. Median sputum eosinophil percentages were 0% (IQR, 0-1.5%) in BE - CRS and 3% (1-12%) in BE + CRS (P = 0.012). Blood eosinophil counts were predictive of sputum eosinophilia (counts ⩾3%; area under the receiver operating characteristic curve, 0.68; 95% confidence interval, 0.50-0.85). Inclusion of CRS improved the prediction of sputum eosinophilia by blood eosinophil counts (area under the receiver operating characteristic curve, 0.79; 95% confidence interval, 0.65-0.94). Methacholine tests were negative in 85.7% of patients in the BE - CRS group and 85.2% of patients in the BE + CRS group (P > 0.99). Specific IgE and skin testing were similar between the groups, but total IgE levels were increased in people with increased sputum eosinophils. Microbiome analysis demonstrated distinct microbiota in nasopharyngeal and airway samples in the BE + CRS and BE - CRS groups, without significant differences between groups. However, interactome analysis revealed altered interactomes in individuals with high sputum eosinophil counts and CRS. Conclusions: Bronchiectasis with CRS is associated with an eosinophilic airway inflammation that is distinct from asthma.

Objective sputum colour assessment and clinical outcomes in bronchiectasis: data from the European Bronchiectasis Registry (EMBARC)

BACKGROUND

A validated 4-point sputum colour chart can be used to objectively evaluate the levels of airway inflammation in bronchiectasis patients. In the European Bronchiectasis Registry (EMBARC), we tested whether sputum colour would be associated with disease severity and clinical outcomes.

METHODS

We used a prospective, observational registry of adults with bronchiectasis conducted in 31 countries. Patients who did not produce spontaneous sputum were excluded from the analysis. The Murray sputum colour chart was used at baseline and at follow-up visits. Key outcomes were frequency of exacerbations, hospitalisations for severe exacerbations and mortality during up to 5-year follow-up.

RESULTS

13 484 patients were included in the analysis. More purulent sputum was associated with lower forced expiratory volume in 1 s (FEV1), worse quality of life, greater bacterial infection and a higher bronchiectasis severity index. Sputum colour was strongly associated with the risk of future exacerbations during follow-up. Compared to patients with mucoid sputum (reference group), patients with mucopurulent sputum experienced significantly more exacerbations (incident rate ratio (IRR) 1.29, 95% CI 1.22-1.38; p<0.0001), while the rates were even higher for patients with purulent (IRR 1.55, 95% CI 1.44-1.67; p<0.0001) and severely purulent sputum (IRR 1.91, 95% CI 1.52-2.39; p<0.0001). Hospitalisations for severe exacerbations were also associated with increasing sputum colour with rate ratios, compared to patients with mucoid sputum, of 1.41 (95% CI 1.29-1.56; p<0.0001), 1.98 (95% CI 1.77-2.21; p<0.0001) and 3.05 (95% CI 2.25-4.14; p<0.0001) for mucopurulent, purulent and severely purulent sputum, respectively. Mortality was significantly increased with increasing sputum purulence, hazard ratio 1.12 (95% CI 1.01-1.24; p=0.027), for each increment in sputum purulence.

CONCLUSION

Sputum colour is a simple marker of disease severity and future risk of exacerbations, severe exacerbations and mortality in patients with bronchiectasis.

[Secondary non-tuberculous mycobacterium infection in patients with bronchiectasis caused by Marfan syndrome]

In this article, we reported a 28-year-old female patient who presented with intermittent hemoptysis, cough, and sputum production. Laboratory tests showed no abnormalities in the blood counts or inflammatory markers, and the sputum cultures were negative. A chest computed tomography scan showed bronchiectasis associated with infection in the middle and lower lobes of the right lung and right pleural thickening. We performed bronchoalveolar lavage by bronchoscopy in the dorsal segment of the right lower lobe and found Mycobacterium avium intracellulare complex (MAC) by Next Generation Sequencing (NGS) of bronchoalveolar lavage fluid (BALF). The patient's symptoms improved significantly after anti-mycobacterium treatment and the extent of infection was reduced on imaging. To further identify the cause of bronchiectasis, the patient is tall and thin, with slender limbs. Cardiac color ultrasound showed the widening of aortic sinus. Her genetic testing of blood samples revealed the gene mutation in the FBN1 gene (c.4349G>A). Based on these results, she was diagnosed with Marfan syndrome.

Inflammatory Molecular Endotypes in Bronchiectasis: A European Multicenter Cohort Study

Rationale: Although inflammation and infection are key disease drivers in bronchiectasis, few studies have integrated host inflammatory and microbiome data to guide precision medicine. Objectives: To identify clusters among patients with bronchiectasis on the basis of inflammatory markers and to assess the association between inflammatory endotypes, microbiome characteristics, and exacerbation risk. Methods: Patients with stable bronchiectasis were enrolled at three European centers, and cluster analysis was used to stratify the patients according to the levels of 33 sputum and serum inflammatory markers. Clusters were compared in terms of microbiome composition (16S ribosomal RNA sequencing) and exacerbation risk over a 12-month follow-up. Measurements and Main Results: A total of 199 patients were enrolled (109 [54.8%] female; median age, 69 yr). Four clusters of patients were defined according to their inflammatory profiles: cluster 1, milder neutrophilic inflammation; cluster 2, mixed-neutrophilic and type 2; cluster 3, most severe neutrophilic; and cluster 4, mixed-epithelial and type 2. Lower microbiome diversity was associated with more severe inflammatory clusters (P < 0.001), and β-diversity analysis demonstrated distinct microbiome profiles associated with each inflammatory cluster (P = 0.001). Proteobacteria and Pseudomonas at phylum and genus levels, respectively, were more enriched in clusters 2 and 3 than in clusters 1 and 4. Furthermore, patients in cluster 2 (rate ratio [RR], 1.49; 95% confidence interval [CI], 1.16-1.92) and cluster 3 (RR, 1.61; 95% CI, 1.12-2.32) were at higher risk of exacerbation over a 12-month follow-up compared with cluster 1, even after adjustment for prior exacerbation history. Conclusions: Bronchiectasis inflammatory endotypes are associated with distinct microbiome profiles and future exacerbation risk.

Nontuberculous mycobacterial (NTM) infections in bronchiectasis patients: A retrospective US registry cohort study

RATIONALE

Longitudinal epidemiological and clinical data are needed to improve the management of patients with bronchiectasis developing nontuberculous mycobacterial (NTM) pulmonary disease.

OBJECTIVES

To describe the epidemiology, patient management, and treatment outcomes of NTM infections in patients with bronchiectasis enrolled in the United States Bronchiectasis and NTM Research Registry (US BRR).

METHODS

This was a retrospective cohort study of patients with bronchiectasis and NTM infections enrolled with follow-up in the US BRR in 2008-2019. The study included patients with ≥1 positive NTM respiratory culture in the 24-month baseline period (baseline NTM cohort) and/or during the annual follow-up visits (incident NTM cohort). Incidence, prevalence, baseline patient characteristics, treatment exposure, treatment outcomes, and respiratory clinical outcomes were described in the baseline NTM cohort, incident NTM cohort, and both cohorts combined (prevalent NTM cohort).

RESULTS

Between 2008 and 2019, 37.9% (1457/3840) of patients with bronchiectasis in the US BRR met the inclusion criteria for this study and were reported to have Mycobacterium avium complex (MAC) and/or Mycobacterium abscessus complex (MABSC) infections. MAC prevalence increased steadily in the US BRR during 2009-2019; incidence was relatively stable, except for a peak in 2011 followed by a slow decrease. MABSC and mixed MAC/MABSC infections were rare. Most patients with bronchiectasis and NTM infections in the registry were female, White, and aged >65 years. The antibiotics administered most commonly reflected current guidelines. In the prevalent cohort, 44.9% of MAC infections and 37.1% of MABSC infections remained untreated during follow-up, and MAC treatment was initiated with delay (>90 days after positive NTM respiratory culture) twice as frequently as promptly (≤90 days after positive NTM respiratory culture) (68.6% vs 31.4%, respectively). The median time from diagnosis to treatment was shorter for MABSC versus MAC infections (194.0 days [interquartile range (IQR) 8.0, 380.0] vs 296.0 days [IQR 35.0, 705.0], respectively). Among patients with MAC infections who completed treatment, 27.6% were classified as cured and 29.6% as treatment failure during the annual follow-up visit window. For MABSC, these proportions were 25.0% and 28.0%, respectively.

CONCLUSIONS

A considerable proportion of MAC and MABSC infections were untreated or treated after initial delay/observation. MABSC infections were more likely to be treated and start treatment sooner than MAC infections. Further longitudinal studies are warranted to evaluate the monitor-with-delay approach and inform clinical guidelines.

A case-control study on the risk factors associated with the occurrence of non-tuberculous mycobacteria pulmonary disease in bronchiectasis patients

OBJECTIVE

The objective of this study is to analyze the risk factors associated with bronchiectasis combined with non-tuberculous mycobacteria pulmonary disease(NTM-PD) and provide a basis for more effective prevention and treatment strategies.

METHODS

The study subjects for this manuscript were patients with bronchiectasis who were admitted to the infection department between January 2021 and June 2023.There were 34 patients with NTM-PD in the observation group, and 52 patients with simple bronchiectasis in the control group. Basic information, imaging features, serum albumin levels, and infection indicators were collected from both groups of patients.Univariate and multivariate logistic regression analysis were performed to analyze the risk factors for NTM-PD in patients with bronchiectasis.

RESULTS

Multivariate logistic regression analysis revealed that bronchiectasis exacerbation occurring at least twice a year(OR = 3.884, 95% CI: 1.200-12.568), involvement of three or more lung lobes with bronchiectasis (OR = 3.932, 95% CI: 1.208-12.800), hypoalbuminemia (OR = 3.221, 95% CI: 1.015-10.219), and the NLR index (OR = 1.595, 95% CI: 1.200-2.119) were significant risk factors for non-tuberculous mycobacteria pulmonary disease in individuals with bronchiectasis (P < 0.05).

CONCLUSION

Patients with bronchiectasis accompanied by NTM-PD present specific risk factors that should be promptly addressed through prevention and treatment.

Comparison of treatment outcomes between intermittent and daily regimens in non-cavitary nodular bronchiectatic-type Mycobacterium avium complex pulmonary disease in relation to sputum smear results: a retrospective cohort study

This study retrospectively analyzed the treatment outcomes of 110 patients with non-cavitary nodular bronchiectatic-type Mycobacterium avium complex pulmonary disease who received intermittent or daily treatment with a three-drug oral antibiotic regimen (i.e., a macrolide, ethambutol, and rifampin) at a tertiary referral center in South Korea. Among these patients, 36 had sputum smear positivity. Of these 36 patients, intermittent treatment led to a lower culture conversion rate than daily treatment [50.0% (8/16) vs 85.0% (17/20), P = 0.034].

Gastroesophageal Reflux Disease Increases Susceptibility to Nontuberculous Mycobacterial Pulmonary Disease

BACKGROUND

Gastroesophageal reflux disease (GERD) is a common comorbidity of nontuberculous mycobacteria (NTM) pulmonary disease (PD). Although GERD is associated with more symptoms and severe disease in patients with NTM PD, whether GERD is associated with an increased risk of NTM PD developing is unknown.

RESEARCH QUESTION

Does GERD influence the development of NTM PD? Are there any factors associated with an increased risk of NTM PD among patients with GERD? What is the impact of NTM PD on the health-care use of patients with GERD?

STUDY DESIGN AND METHODS

Data from the Korean National Health Insurance Service National Sample Cohort between 2002 and 2015 were used. The incidence and risk of NTM PD were compared between patients with GERD (GERD cohort; n = 17,424) and patients matched for age, sex, type of insurance, and Charlson Comorbidity Index (matched cohort; n = 69,696). Using the GERD cohort, the factors associated with incident NTM PD also were evaluated.

RESULTS

During a median follow-up duration of 5.1 years, the age- and sex-adjusted incidence of NTM PD was significantly higher in the GERD cohort (34.8 per 100,000 person-years [PY]) than in the matched cohort (10.5 per 100,000 PY; P < .001), with a subdistribution hazard ratio (HR) of 3.36 (95% CI, 2.10-5.37). Regarding risk factors associated with NTM PD, age of 60 years or older (adjusted HR, 3.57; 95% CI, 1.58-8.07) and bronchiectasis (adjusted HR, 18.69; 95% CI, 6.68-52.28) were associated with an increased risk of incident NTM PD in the GERD cohort. Compared with patients with GERD who did not demonstrate NTM PD, those with NTM PD showed higher all-cause (13,321 PY vs 5,932 PY; P = .049) and respiratory disease-related (5,403 vs 801; P = .011) ED visits or hospitalizations.

INTERPRETATION

GERD is associated with an increased incidence of NTM PD. Older age and bronchiectasis are risk factors for NTM PD in patients with GERD. NTM PD in patients with GERD is associated with increased health-care use.

Global prevalence of non-tuberculous mycobacteria in adults with non-cystic fibrosis bronchiectasis 2006-2021: a systematic review and meta-analysis

OBJECTIVE

To accurately estimate the global prevalence of non-tuberculous mycobacteria (NTM) in adults with non-cystic fibrosis (non-CF) bronchiectasis and to determine the proportion of NTM species and subspecies in clinical patients from 2006 to 2021.

DESIGN

Systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA SOURCES

Medline, Embase, Cochrane Library and Web of Science were searched for articles published between 2006 and 2021.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included all the prospective or retrospective studies without language restrictions and all patients were adults (≥18 years of age) with non-CF bronchiectasis. The studies estimated the effect size of the prevalence of NTM with a sample size ≥40, and patients were registered in and after 2006.

DATA EXTRACTION AND SYNTHESIS

Two reviewers screened the titles, abstracts and full texts independently. Relevant information was extracted and curated into tables. Risk of bias was evaluated following the Cochrane Collaboration's tool. Meta-analysis was performed with software R Statistics V.3.6.3 using random effect model with 95% CI. I² index and Q statistics were calculated to assess the heterogeneity, and mixed-effects meta-regression analyses were performed to identify the sources of heterogeneity. The proportions of NTM subspecies were examined using Shapiro-Wilk normality test in R.

RESULTS

Of all the 2014 studies yielded, 24 met the inclusion criteria. Of these, 14 were identified to be randomised controlled studies and included for an accurate estimation. The global prevalence of NTM in adults with non-CF bronchiectasis from 2006 to 2021 was estimated to be approximately 10%, with great variations primarily due to geographical location. Mycobacterium avium complex was the most common subspecies, followed by Mycobacterium simiae and Mycobacterium gordonae.

CONCLUSIONS

The prevalence of NTM in adults with non-CF bronchiectasis has been on the rise and the most common subspecies changed greatly in recent years. More cohort studies should be done in many countries and regions for future estimates.

PROSPERO REGISTRATION NUMBER

CRD42020168473.

Multidrug-resistant Pseudomonas aeruginosa is predisposed to lasR mutation through up-regulated activity of efflux pumps in non-cystic fibrosis bronchiectasis patients

Background

Multidrug-resistant (MDR) Pseudomonas aeruginosa is a frequent opportunistic pathogen that causes significant mortality in patients with non-cystic fibrosis bronchiectasis (NCFB). Although the quorum sensing (QS) system is a potential target for treatment, lasR mutants that present with a QS-deficient phenotype have been frequently reported among clinical P. aeruginosa isolates. We aimed to investigate whether antibiotic resistance would select for lasR mutants during chronic P. aeruginosa lung infection and determine the mechanism underlying the phenomenon.

Methods

We prospectively evaluated episodes of chronic P. aeruginosa lung infections in NCFB patients over a 2-year period at two centers of our institution. QS phenotypic assessments and whole-genome sequencing (WGS) of P. aeruginosa isolates were performed. Evolution experiments were conducted to confirm the emergence of lasR mutants in clinical MDR P. aeruginosa cultures.

Results

We analyzed episodes of P. aeruginosa infection among 97 NCFB patients and found only prior carbapenem exposure independently predictive of the isolation of MDR P. aeruginosa strains. Compared with non-MDR isolates, MDR isolates presented significantly QS-deficient phenotypes, which could not be complemented by the exogenous addition of 3OC12-HSL. The paired isolates showed that their QS-phenotype deficiency occurred after MDR was developed. Whole-genome sequencing analysis revealed that lasR nonsynonymous mutations were significantly more frequent in MDR isolates, and positive correlations of mutation frequencies were observed between genes of lasR and negative-efflux-pump regulators (nalC and mexZ). The addition of the efflux pump inhibitor PAβN could not only promote QS phenotypes of these MDR isolates but also delay the early emergence of lasR mutants in evolution experiments.

Conclusions

Our data indicated that MDR P. aeruginosa was predisposed to lasR mutation through the upregulated activity of efflux pumps. These findings suggest that anti-QS therapy combined with efflux pump inhibitors might be a potential strategy for NCFB patients in the challenge of MDR P. aeruginosa infections.

Chest Computed Tomography Features of Nontuberculous Mycobacterial Pulmonary Disease Versus Asymptomatic Colonization: A Cross-sectional Cohort Study

BACKGROUND

Asymptomatic colonization by nontuberculous mycobacteria (NTM) found in sputum isolates are commonly encountered and clinicians lack a biomarker for prognosticating the risk of transition asymptomatic colonization to active clinical disease. Chest computed tomography (CT) imaging is commonly obtained in this patient population and may serve a role for this purpose.

METHODS

We conducted a single-center, cross-sectional study of patients followed in the NTM clinic at our center between August 2019 and August 2020. All patients had a history of NTM isolated from their airways and were cohorted as either nontuberculous mycobacteria-pulmonary disease (NTM-PD) if they met ATS/IDSA guidelines for treatment or as nontuberculous mycobacteria-colonized (NTM-C) if they did not meet ATS/IDSA criteria for NTM treatment. Patients with a chest CT were included in the analysis and CT scans were assessed for features including bronchiectasis, nodules, and cavities. Bronchiectasis severity was calculated using the modified Reiff scoring system. Univariate analyses were conducted to compare patients with NTM-C and NTM-PD.

RESULTS

Eighty-four patients were included in the analysis and 27 were classified as NTM-C and 57 as NTM-PD. NTM-PD patients had a greater median number of lung lobes affected by bronchiectatic airways (6 [1] NTM-PD vs. 5 [3] NTM-C P=0.005) and a greater frequency of cystic bronchiectasis (17.5% NTM-PD vs. 0% NTM-PD, P=0.016). Bronchiectasis severity was higher for NTM-PD patients (7 [9] NTM-PD vs. 5 [1.5] NTM-C, P<0.001).

CONCLUSIONS

Patients with NTM-PD have greater bronchiectatic airway involvement and the forms of bronchiectasis present are more severe compared with NTM-C patients. In addition, cavitation of lung parenchyma was a radiographic feature solely associated with NTM-PD. Features identified on chest CT may be useful as a prognostic biomarker for the risk of transition from NTM-C to NTM-PD.

Microbiology rapid on-site evaluation: a better method for Mucoid Pseudomonas Aeruginosa diagnosis in bronchiectasic patients

OBJECTIVE

The aim of this study is to find an accurate and fast method to diagnose the pathogen of bronchiectasis.

PATIENTS AND METHODS

Ten bronchiectasic patients diagnosed with Mucoid Pseudomonas Aeruginosa (MPA) in the past two years were analyzed. Accuracy and time were compared between microbiology rapid on-site evaluation (M-ROSE) and sputum bacterial culture.

RESULTS

The accuracy rate of M-ROSE in the patients is 100% consistent with bacterial culture results. The average time of M-ROSE is about 4.3 min, which is over 1000 times shorter than that of sputum bacterial culture.

CONCLUSIONS

M-ROSE may be a better method for etiological diagnosis of MPA.

Exploring factors associated with acquisition and chronicity of infection in bronchiectasis: A population-based study

INTRODUCTION

Chronic infection is associated with adverse outcomes among people with bronchiectasis. However, it is not known which factors are associated with a bacterial infection, and with persistence of an infection after the first episode. We aimed to determine factors associated with a new infection and with chronicity of Pseudomonas aeruginosa (PA) and H. influenzae (HI), the most common organisms in bronchiectasis infection.

METHODS

Using an Israeli population database, we identified individuals diagnosed with bronchiectasis. Cox proportional hazard models were used to assess risk factors for first isolation and Logistic regression for chronicity of infection after a first isolation of PA and HI.

RESULTS

We included 1305 people with a median of 5 respiratory samples per individual. PA was initially isolated in 297 people, of whom 97 (33%) developed chronic PA infection. HI was newly identified in 169 people, of whom 39 (23%) developed chronic infection (p = 0.029). Factors associated with increased risk of a new infection with PA were COPD (HR 1.87 [1.52-2.28], previous isolation of HI (HR 1.38 [1.07-1.78]), and alcohol abuse (HR 2.22 [1.13-4.3]). Younger age was associated with increased risk of HI infection, while COPD was associated with a lower risk of HI infection. Prescription of an anti- PA antibiotic was associated with chronic PA after a new infection (OR = 1.8 [1.09-2.9], p = 0.02). A landmark analysis showed that survival was worse in people with chronic PA infection vs. single or intermittent infection (Log rank: p = 0.034) CONCLUSIONS: Younger age and presence of PCD are associated with a new isolation of HI. A new infection with PA is associated with previous HI infection, PCD, COPD, and alcohol abuse. Unexpectedly, treatment with appropriate anti-PA antimicrobials was not associated with a reduced risk of chronicity.

Bronchiectasis with secondary pulmonary infection in a child: A case report

RATIONALE

Although bronchiectasis is conventionally considered a chronic pulmonary disease of adulthood, knowledge of pediatric bronchiectasis not related to cystic fibrosis started to emerge. Limited information in this field is available and the management is based on expert opinion.

PATIENT CONCERNS

An 8-year-old girl admitted for 7 days history of wet cough, purulent fetid sputum, shortness of breath and low-grade fever. The wet cough has presented for the past 4 years, during which she had frequent hospitalization for recurrent lower respiratory tract infections.

DIAGNOSIS

Chest high-resolution computerized tomography revealed diffuse bronchial dilations accompanied by inflammation in the bilateral lung fields. Microbiologic investigation for bronchoalveolar lavage fluid was positive for Pseudomonas aeruginosa.

INTERVENTIONS

With a working diagnosis of bronchiectasis with secondary pulmonary infection, sensitive cefoperazone-sulbactam was administrated for 14 days with gradual improvement of clinical symptoms. Bronchoscopy washing substantially soothed the symptoms, reducing the cough and sputum volumes.

OUTCOMES

The child was discharged after 14 days, and treated on long-term prophylactic antibiotic use (amoxicillin-clavulanic acid, 20 mg/kg/d, ≥ 4 weeks).

LESSONS

Although bronchiectasisis are condition in childhood, the diagnosis is suspected in children with persistent wet or productive cough, and should be confirmed by a chest high-resolution computerized tomography scan. Antibiotics and airway clearance techniques represent the milestones of bronchiectasis management although there are only a few guidelines in children.

Exacerbations and Pseudomonas aeruginosa colonization are associated with altered lung structure and function in primary ciliary dyskinesia

BACKGROUND

Recurrent bacterial infections of the respiratory tract are one of the major clinical features of the primary ciliary dyskinesia (PCD), a rare genetic disease due to malfunctioning of motile cilia. Chronic infections and persistent inflammation of the respiratory system result in progressive lung disease. Aim of the study was to highlight the main factors associated with clinical, functional and anatomical deterioration in PCD patients.

METHODS

We retrospectively analyzed data from 58 patients with PCD, 37 adults and 21 children. The demographic and clinical data, forced expiratory volume at 1 s (FEV1) and forced vital capacity (FVC), sputum microbiology and imaging results (chest CT scores-modified Bhalla) were recorded. Patients were stratified according to the number of exacerbations (< 2/year vs ≥ 2/year) and chronic Pseudomonas aeruginosa (PA) colonization. The possible correlations between lung function and chest CT scores were assessed; we also evaluated the correlation between these parameters and the severity scores for bronchiectasis (BSI, FACED and e-FACED).

RESULTS

Chest CT scores showed a significant correlation with FEV1 (p = 0.0002), age (p <  0.0001), BMI (p = 0.0002) and number of lung lobes involved (p <  0.0001). PA colonization had an overall prevalence of 32.6%: no significant difference in FEV1 between PA colonized and non-colonized patients was found (p = 0.70), while chest CT score was significantly worse in chronic PA colonized patients (p = 0.009). Patients with a high number of exacerbation (≥ 2/year) were older (p = 0.01), had lower FEV1 (p = 0.03), greater number of lobes involved (p < 0.001) and worse CT score than patients with low number of exacerbations (p = 0.001); they also had higher prevalence of PA chronic bronchial infection (33.3% versus 13.6%, p = 0.10). Multivariable linear regression analyses adjusted for gender, age and BMI showed positive associations between PA colonization and number of exacerbations with severity of disease (number of lobes involved, CT score, BSI, FACED, and e-FACED).

CONCLUSIONS

In our PCD population the number of exacerbations (≥ 2/year) and PA colonization were the two most relevant factors associated with severity of disease.

Characterization of non-tuberculous mycobacterial pulmonary disease in Nanjing district of China

BACKGROUND

Environmental bacteria, nontuberculous mycobacteria (NTM), are recognized as one of the major human infection pathogens. NTM are prone to be mistaken as multidrug-resistant Mycobacterium tuberculosis and challenge our fight against TB. In addition, treatment of NTM per se is intractable. Remarkably, the distribution of NTM pathogenic species is geographically specific. Thus, it is very important to summarize the prevalent features and clinical symptoms of NTM pulmonary disease. However, In Nanjing district, southeast China, there is no such a report.

METHODS

Through investigating electronic medical records and analyzing data of clinical examination system (Lis), we retrospectively summarized the NTM species from 6012 clinical isolates from May 2017 to August 2018, and analyzed the association between NTM species and clinical symptoms.

RESULTS

Of 6012 clinical specimens, 1461 (24.3%) could grow in the MGIT 960 broth. Among these positive isolates, 1213 (83%) were M. tuberculosis, 22 (1.5%) were M. bovis, and 226 (15.5%) were NTM. After deducting redundancy, those NTM specimens were confirmed from 154 patients, among which, 87 (56.5%) patients met the full ATS/IDSA NTM disease criteria. The most common etiologic agent was M. intracellulare (70.1%). NTM infection was associated with age, based on which 68.6% male patients and 77.8% female patients were over 50 years old. The older patients were more likely to have hemoptysis, but the younger patients were more likely to manifest chest congestion. Male patients were more likely to have shortness of breath and females were more likely to have hemoptysis. The most common radiographic presentation of NTM pulmonary disease was bronchiectasis, accounting for 39.1%. Remarkably, multiple and thin-walled cavities were outstanding. The most frequent comorbidity of NTM disease was previous tuberculosis (64%), followed by clinical bronchiectasis (19.5%), HIV (19.5%), and 6.9% chronic obstructive pulmonary disease (COPD). There was no association between NTM species and clinical symptoms.

CONCLUSION

This study retrospectively investigated the prevalence of NTM pulmonary disease in Nanjing district, southeast China. Similar to Beijing area, north China, M. intracellulare was the major pathogenic NTM species. Clinical symptoms of the disease were not species-specific. Previous TB and HIV infection immensely enhanced risk of NTM disease.

[Experience with nebulised colistin in patients with non-cystic fibrosis bronchiectasis colonised with Pseudomonas aeruginosa]

OBJECTIVE

Chronic colonisation/infection by Pseudomonas aeruginosa of the bronchiectasis is related to a faster deterioration of lung function, an increase in the number of exacerbations and a higher morbidity and mortality. Nebulised colistin decreases bacteria load. Therefore, a reduction in the number and in the severity of exacerbations and a delay of pulmonary decline is expected. The main objective is to evaluate if the treatment with nebulised colistin, for at least 6 months reduces the number of admissions and visits to the emergency department.

METHODS

Observational, retrospective and non-interventionist study carried out in an organizational structure with an integrated management. Patients with non-cystic fibrosis bronchiectasis colonised / infected by P. aeruginosa, older than 18 years, were selected. Patients must have received nebulized colistin during at least 6 months. Clinical, microbiological and therapeutic data from the patients were collected from the SERGAS computerized clinical history (IANUS® v.4.20.0503) and the electronic prescription, which were divided into two time periods: 1) 6 months pre-treatment and during the treatment and 2) 12 months pre-treatment and during the treatment, in those who completed 1 year of treatment.

RESULTS

Forty-four patients were included and of these, 29 (65.9%) had a follow-up of 12 months. The use of nebulized colistin decreased significantly the number of visits to the emergency (at 6 months), the frequency and duration of hospitalizations admissions (at 6 and 12 months), the antibiotic consumption (at 6 and 12 months) and the positive cultures. The treatment was well tolerated in almost all patients.

CONCLUSIONS

The treatment with nebulised colistin during 6 and 12 months of non-cystic fibrosis bronchiectasis, colonised/infected by P. aeruginosa, seems beneficial for the patient, from the clinical and quality of life point of view, and could reduce the economic cost of the process.

Rapid resolution of reversible bronchiectasis after Mycoplasma pneumoniae pneumonia in an adult: A case report

RATIONALE

Bronchiectasis results when inflammatory and infectious damage to the bronchial and bronchiolar walls leads to a vicious cycle of airway injury. On the basis of the classic characteristic, that is, permanent bronchial dilatation, bronchiectasis is generally considered irreversible in the adult population.

PATIENT CONCERNS

A 21-year-old woman presented to our hospital with a 9-day history of productive cough and fever.

DIAGNOSIS

Bronchiectasis after Mycoplasma pneumoniae pneumonia.

INTERVENTIONS

The patient was treated with azithromycin for 7 days.

OUTCOMES

The bronchial dilatation resolved as evidenced by sequential chest high-resolution computed tomography 7 days and 1 month later, respectively.

LESSONS

Although complete disappearance is quite rare in adult, this case demonstrated that bronchial dilatation might resolve completely in such a fascinating short period of time if receiving adequate and timely regimens.